OBJECTIVES: I. To investigate the potential usefulness of well-characterized immune serum in the treatment of animal tumors and to define the mode of action of these sera in conferring immunity to tumor transplants. II. To study the immunological and virological aspects of Herpesvirus saimiri (HVS) oncogenesis in nonhuman primates as a model for Epstein-Barr virus (EBV) infection in man. III. To collaborate with other investigators within and outside NIH on problems of mutual interest.